Shuttle spring



Jan. 3, 1956 F. E. O'NEIL 2,729,247

' SHUTTLE SPRING Filed March 7, 1955 INVENTOR. FRANCIS E. O'NEIL.

i zd aish A TTORNE Y United States Patent SHUTTLE SPRING Francis E. ONeil, Hopedale, Mass, assignor to Draper Corporation, Hopedale, Mass., a corporation of Maine Application March 7, 1955, Serial No. 492,654

2 Claims. (Cl. 139207) This 'invention relates to improvements in shuttle springs and the manner of retaining the spring in the shuttle.

It is an object of the invention to devise a shuttle spring and so mount it in a shuttle body that the spring itself may be stronger in that its holding power is increased, to provide deeper grooves in which the bobbin rings may be better seated and to hold the spring more securely in the body of the shuttle, all without employing spring stock of thicker gage.

Shuttles for automatic bobbin changing looms have fixed therein a spring which grips a bobbin carrying the filling supply. These springs have a U-shaped shank whch fits into a cavity machined from the shuttle material and held therein by a cross bolt and a spring cover. Shuttles are made as large as practicable and it is considered better practice to employ as large a filling supply in the shuttle as can be carried. With increased speeds of operation, the demands upon the shuttle spring have become greater and failure may take several forms, e. g., the spring may break, the grooves wear excessively or the spring itself become loosened in the shuttle. In fact, all three of these are rather common sources of annoyance.

According to the invention herein described and claimed, the above mentioned sources of trouble are to a great extent alleviated. A spring of the same general type as is ordinarily employed is formed with an outwardly directed, rather shallow corrugation running about the entire periphery of the spring. This corrugation serves several purposes and contributes advantages all as will be explained more fully in the following detailed description of a preferred embodiment of the invention as illustrated in the accompanying figures of drawing, wherein:

Fig. l is a plan view showing the invention applied to a shuttle.

Fig. 2 is a plan view of a spring according to the invention.

Fig. 3 is an elevation of that spring.

Fig. 4 is a section at line 4-4, Fig. 2.

Fig. 5 is a section at line 5--5, Fig. 2.

Now referring to Fig. 1, a spring is mounted in a shuttle body 11 of wood, plastic orother material and held in place by the usual cross bolt 12 and by a spring cover 13 through which a screw 14 is passed. The spring comprises a fairly rigid, U-shaped shank 15 and bobbin holding or gripping jaws 16 and 17. A wooden or other filler block 18 is interposed between the side members of the U-shaped shank and resists the clamping forces of the holding means. Jaws 16 and 17 are provided with 2,729,247 Patented Jan. 3, 1956 grooves for receiving the rings 19 at the butt of the usual filling bobbin 20.

, Now referring to Figs. 2-5, the spring 10 is shown to an enlarged scale and has a corrugation 21 extending entirely about its periphery. This corrugation is generally centrally positioned at the jaws so its center is substantially in the same plane as the center for the grooves. It is also rather shallow, yet does stifien the spring noticeably without rendering it too rigid as is the case if its gage is increased to any appreciable extent. The U-shaped shank is stiffened to such extent that more of the spring action occurs at the jaws and as a result, breakage at the sharp bend of the U is lessened. Further, the grooves may be cut deeper without leading to undesirable results. It is well known that springs frequently break at one of the grooves. The corrugation as seen in Fig. 5, gives more material, even with a deeper groove. The strength is increased and the holding characteristics of the jaws also improved.

Normally, the cavity into which the shank is inserted aifords lateral restraint while the only forces holding the spring against vertical displacement are those due to the cross bolt, the support at the bottom and the spring cover. Springs do frequently loosen and the cavity formed in the shuttle body is, accordingrto the invention, grooved at the sides and curved end to receive the corrugation tightly. This gives added holding forces which prevent loosening and the obvious undesired results thereof.

Thus, by a simple change in form of the section of the spring it becomes possible to improve both the spring and the shuttle spring combination.

While one embodiment of the invention has been disclosed, it is to be understood that the inventive concept may be carried out in a number of Ways. This invention is, therefore, not to be limited to the precise details described, but is intended to embrace all variations and modifications thereof falling within the spirit of the invention and the scope of the claims.

I claim:-

1. A shuttle having in combination a shuttle body and a bobbin supporting spring, said spring having bobbin gripping jaws, spaced grooves formed interiorly of said jaws adjacent their ends and a U-shaped shank portion by which said supporting spring is held in said shuttle body, said spring having extending about its entire outer periphery and substantially on a plane with the centers of said grooves, an outwardly directed, arcuate corrugation, and means in said shuttle defining a cavity for receiving said U-shaped shank of the spring, said cavity being formed with an indentation complementary to the said corrugation for tightly embracing it when the spring is inserted therein.

2. A shuttle having in combination a shuttle body and a bobbin supporting spring, said spring having bobbin gripping jaws, spaced grooves formed interiorly of said jaws adjacent their ends and a U-shaped shank portion by which said supporting spring is held in said shuttle body, said spring having extending about its entire outer periphery an outwardly directed, arcuate corrugation, and means in said shuttle defining a cavity for receiving said U-shaped shank of the spring, said cavity being formed with an indentation complementary to the said corrugation for tightly embracing it when the spring is inserted therein.

No references cited. 

